1. Field of the Invention and Related Art Statement
This invention relates to a spectral diagnosing apparatus with an endoscope wherein spectral characteristics of an object are presumed by using several kinds of filters. Recently, an endoscope is extensively use whereby organs within a body cavity can be observed by inserting an elongate insertable section into a body cavity or, as required, various therapeutic treatments can be made by using treating instruments inserted through a treating instrument channel.
A conventional endoscope apparatus is of a formation as is shown in FIG. 1. As shown in FIG. 1, a conventional endoscope apparatus 201 comprises an electronic endoscope 204 whereby an elongate insertable section 203 is inserted through a body cavity of a living body 202, a video processor 206 having a video signal processing mechanism is connected to this electronic endoscope 204 through a connector 205A of a universal cord 205, a video signal color-displaying monitor 207 is connected to this video processor 206 and a sucker or aspirator 209 is connected to the electronic endoscope 4 through a cable 208 branched from the above mentioned connector 205A.
The flow of a video signal of this endoscope apparatus 201 is shown in FIG. 2. A light emitted from a lamp 211 is separated sequentially in time into respective wavelength ranges of red (R), green (G) and blue (B) by a rotary filter 213 rotated and driven by a motor 212, has the light amount regulated by a mesh filter 214 as an iris and is then incident upon the entrance end of a light guide 215 of the above mentioned electronic endoscope 204. This frame sequential illuminating light is input to the tip section of the above mentioned electronic endoscope 204 by the above mentioned light guide 215, is emitted from this tip section and is radiated to an object. The light reflected from the object from the illuminating light, is made by an imaging optical system to form an image on a CCD 221 provided in the tip section of the endoscope. A picture image signal from this CCD 221 is input into an amplifier 222 and is amplified to a voltage level in a predetermined range. The output of this amplifier 222 is input into a .gamma.--compensating circuit 223 and is.gamma.--compensated there. For an RGB frame sequential system, this .gamma.--corrected signal is converted into a digital signal by an A/D converter 224 and is then stored respectively in an R memory 226R, G memory 226G and B memory 226B corresponding to the respective signals of R, G and B through a switching switch 225. The picture image signals stored in these respective memories 226R, 226G and 226B are output by the timing of a TV signal and are converted into analogue signals. The respective picture image signals converted into analogue signals are transmitted to the respective signal output ends of R, G and B together with a synchronizing signal SYNC generated by a synchronizing signal generating circuit 232. The thus obtained RGB signals are displayed on the monitor 207 shown in FIG. 1 to make an endoscope observation.
A video signal from the above mentioned amplifier 222 is input into an iris regulating mechanism section 216 consisting of an integrating circuit 217 and iris servo section 218 to regulate an exposure amount. In this iris regulating mechanism section 216, first the respective signals of R, G and B are integrated by the above mentioned integrating circuit 217 and then the integrated respective signal values are transmitted as light amount values of one picture surface to the iris servo section 218. In this iris servo section 218, the mesh filter 214 is rotated by controlling the motor 219 based on the light amount values to regulate the exposure amount.
The above mentioned electronic endoscope apparatus 201 is further provided with a controlling signal generating circuit 231 for controlling the address of the picture image signal and the timing when transmitting it. This controlling signal generating circuit 231 is connected to the above mentioned switching switch 225, respective memories 226R, 226G and 226B, synchronizing signal generating circuit 232 and motor 212 to input controlling signals to these respective elements.
Thus, in the prior art example, the visible region section is divided into three regions of R, G and B and spectral characteristics of a living body are integrated within the respective regions to form a video signal.
Therefore, minute variations in the spectral characteristics of the living body will be lost in the integrating step and it has been difficult to detect the difference between the normal part and affected part of the living body. Also, when enhancing colors, minute variations will not be able to be taken from the R, G and B signals. Therefore, it has been difficult to make a high precision treatment.
In the publication of a Japanese Patent Publication No. 55420/1982, a picture image of a specific wavelength obtained by transmitting a reflected light from an inspected object by using a half transmitting mirror, transmitting filter and reflecting mirror is obtained by an imaging tube and is processed with a color encoder to obtain a blue color picture image, green color picture image and red color picture image which are composed to obtain a picture image having a strong contrast to make it easy to distinguish the normal part and the abnormal part from each other.
In this prior art example, since all the light within the visual field is utilized for the measurement by contacting the endoscope tip section with the living body mucous membrane, no accurate data of the affected part of a size smaller than the visual field will be obtained and, since the visual field at the time of the measurement can not be secured by contacting, the record of the measured part will not be left in a photograph or the like and will not be able to be utilized later in conference or the like of the doctors themselves within the hospital. A tricolor analyzed picture image is only obtained with the half transmitting mirror or the like and a visible picture image is only made easy to see.
In a Japanese Patent Application No. 260015/1987 of the present assignee, in an electronic endoscope of a frame sequential system sequentially illuminating with a blue color light, green color light and red color light, a chromaticity value is calculated from the blue color light, green color light and red color light information of a part of the visual field and is output to a CRT to be used to determine the normal part and the abnormal part.
In this related art example, as the chromaticity value is determined by measuring and calculating colors from the electromotive force of the CCD by the blue color light, green color light and red color light of the reflected light of a part of the visual field designated on the monitor by a keyboard, in the medical treatment and diagnosis in which the variation on the adjacent boundary or the manner in the area in a range are important, each point must be measured, the diagnosing time will be long and an improvement must be made.
In U.S. Pat. No. 4,651,743, there is disclosed a method wherein different wavelengths are sequentially radiated to a tissue and the light transmitted through the tissue are sensed with a video system to obtain information relating to the tissue.
In this prior art example, as the light transmitted through the tissue are utilized, the information of only the object part can not be obtained and, by the information of the parts other than the object part, the required information will be diluted or will be made difficult to distinguish.
When using the transmitted light, the data obtained by the shape and size of the object will be different and will be difficult to utilize for diagnosis.